Truck shudder

I just replaced the carrier bearing on mine at about 78K miles. The indicator for me was a high pitched whine at speed that didn't change under acceleration or deacceleration. (The noise did go away after unhooking the rear driveshaft and dragging myself around by the front for about 5 miles. You might consider this during your troubleshooting.) Visual inspection of the carrier bearing revealed nothing, but as soon as I spun it by hand off the truck I could tell it wasn't right.

Sounds like a u-joint or slip spline, but because you just had transmission work, I wouldn't be surprised if you had a torque converter issue either.

Matt

It sounds like converter clutch slippage to me. Gary?

I was going to say replace the u-joints and get on with life...................sounds like a bad joint, it only vibrates with no-load on it

Although none of them seem loose, I'm going to replace them all and have that worry out of the way....they are the originals.

Thanks for the ideas,

Spdloader

check with Ford, some of those need a different center-support bracket

Yep, it's a two piece. I've had it out, checking it, but not apart. Nothing seems loose, OR stiff.

Spdloader

||> It feels a little like a bad u-joint or carrier bearing, but they seem ||fine ||> to the eye. ||>

||> A little pressure on the throttle will stop it, and I don't notice it at ||all ||> with the cruise "off". ||>

||> It has a new transmission and torque converter, with less than 2000 miles. ||I ||> noticed this problem about 500 miles ago. (About a week). ||>

||> '99 F350, 7.3 PSD with 87,000 miles ||> SuperCrew, 4X4, Dually. ||> Hypertech Stage III tuner set at Stage One currently. ||> Banks Induction Setup ||>

||>

||> Anyone with a similar problem? ||>

||> Ideas? ||>

||> Spdloader ||>

||>

|| ||

Rex in Fort Worth

Replaced all three ujoints, and carrier bearing assy. Nothing blaringly wrong visually, but with 86,000, and constantly pulling with it, I thought it won't hurt.

Anyway, the shudder didn't go away, and it didn't change. Still there when the truck "unloads" at the top or bottom of an incline, then goes away when the truck starts to pull again.

Axle bearings checked as well, with no problems detected, in fact they looked as good as new.

It's almost like fuel being fluttered to the injectors at a rhythmic rate, but it can be felt in the seat and steering wheel equally. It'll even affect your voice if talking, kind of like riding in a helicopter, if any have had that experience.

Probably taking it back to the dealer, to rule out problems with the new trans, torque converter.

Spdloader